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Presidential Address: Navigation in Aerial Commerce
Published online by Cambridge University Press: 21 October 2009
Extract
Whatever the word ‘navigation’ is taken to mean, it must, etymologically, be something one does to a ship. What a pity that the name ‘airship’ was given so early in the evolution of aviation to its dinosaurs! The modern airliner is truly a ship of the air. There was a move, half a century ago, to coin the word ‘avigation’ but, apart from the obvious retort that, if ‘navigation’ is of ships, ‘avigation’ is strictly for the birds, the term ‘air navigation’ had already been established by the International Convention on Air Navigation and the Air Navigation Acts by which Parliament legislates on aviation in general and its commercial application in particular.
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- Copyright © The Royal Institute of Navigation 1986
References
NOTES AND REFERENCES
1 An extant copy of the sailing directions is dated January 1296 by the copyist. See Motzo, B. R. (1947) II Compasso da Navigare, Cagliari-Universitá.Google Scholar
2 It has been observed that men are rarely so innocently employed.Google Scholar
3 Cf. Goedel's theorem in mathematics and the Indeterminancy Principle in physics.Google Scholar
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11 Normally of course headwind increases the optimum speed (Mach number for maximum range of a jet may increase by 004 against a jet stream if constrained to one flight level). Headwinds also reduce the optimum altitude and at low altitudes max c.r.p.m. on a Britannia could produce speeds in excess of V no, a structural speed limit.Google Scholar
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13 By a bilateral agreement between the UK and the USA after World War II, the capacity to carry traffic between the two nations was divided equally between the carriers designated by each country who were required to offer a common fare structure approved by both countries. As the airlines of other nations started or re-started, these principles became generalized and so extended that the permissible content of an economy class sandwich became a matter of hot debate. Airlines therefore competed almost entirely in terms of aircraft type in an era of rapidly developing product quality, from the unpressurized, 180 kt, 2000 n.m. range DC4 to the Boeing 747 in 22 years. No one could afford anything but the latest. The consequent financial, economic and technical pressures had far-reaching and enduring effects on world transport as a whole and several other industries. There have been no comparable competitive pressures to solve navigation problems since all suffer equally.Google Scholar
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17 I have ignored Concorde which sadly accounts for perhaps 0 1 per cent of world air traffic.Google Scholar